The pfile attribute is a pointer to a recource that contains filenames of patches. The format of this recource is one filename per line optionally followed by a semi-colon (;) and switches for the patch program.

patch_single() checks if the pfile attribute is a plain scalar or a ref to a scalar, array, glob. In the first case this is taken to be a filename. A GLOB-ref is a filehandle, the other two are taken to be literal content.

patch_multi() checks the pfile attribute is a plain scalar or a ref to a scalar, array, glob. In the first case this is taken to be a filename. A GLOB-ref is a filehandle, the other two are taken to be literal content.